Photographic developers containing 8-hydroxyquinolines



Patented Oct. 12 1954 irnoxrojoaarnro'nsvrnornns ,.CONTAIN1NG IT'8-HYDR0XYQU'IN0LINES rRichard .':Hcnn.;and John pany, Rochester, N. Y.

Jersey 'I. Qrabtrce, R h- ;-,;assignors to Eastman Kodak iQomacorporation of New Nomrawing. Application March =14, 1952, [Serial No.2763376 4 Claims. j9588) This invention relates -.to,photography andparcularly to photographic developers having re- .duced tendency tooxidation caused by heavy metals. i p I} "Fog in photographic emulsionsis produced 1n several ways, one

.ofthe developer'when the emulsion is exposed to the air while wet withU type which is known as'aerialfog OCGUIS'ChlBflY developer. Fog of thisor are otherwise unsatisfactory.

It is therefore an tion to provide photographic developers whichaccomplished by incorporating in the developing solution an8-hydroxyquinoline especially an B-hydroxyquinoline-S-sulfonic acid.

The developing solutions which we propose to use contain a silver orequivalent material such as potassium bisulfite, and an8-hydroxyquinoline. Among the 8-hydroxyquinolines which may 'be used forthis purpose are 8-hydroXyquinoline-5-sulfonic acid, 7-chloro-8-hydroxyquinoline-5-sulfonic acid, 7-bromo-8-hydroxyquinoline-5-sulfonic acid and S-methyl 8 hydroxyquinolinesulfonic acid. The developing solution is an alkaline solution tenalkaline;material such as ghydroxide- 'or sodium tsimay-alsobe present.v I The :following examples illustrate developer formulas constituted;according to our (invention.

Example! 2-amino-fi-diethylaminotoluene monohydrochloride 3.0 Sodiumcarbonate (mono) 20.0 Potassium bromide 2.0

8-hydroxyquinoline-5-sulfonic acid 0.25 Water to 1 liter.

Example I! Grams Elon 5.0 Sodium sulfite 100.0 Sodium carbonate 2.5Ethylenediamine sulfate 12.0 8-hydroxyquinoline-5-sulfonic acid 0.25Water to 1 liter.

Example III Grams Hydroquinone 2.5 on 5.0 Sodium sulfite 100.0 0 Sodiummetaborate 20.0 Ethylenediamine tetracetic acid 5.08-hydroxyquinoline-sulfat 1.0 Water to 1 liter.

The B-hydroxyquinolines developer in amounts varying from of two partsof without the 8-hydroxyquinoline-5-sulfonic acid decreased the aerationlife to a vided air bubbles 8-hydroxyquinoline-5-sulfonic acid wasaeration life was restored to its normal of 24 A similar effect wasobserved in of Example IH.

The color developer of Example I shows espe- 3. A photographicdeveloping solution having cially good aeration life and is used fordevelopreduced tendency to oxidation caused by heavy ing an emulsioncontaining color couplers, for exmetals and capable of forming a coloredimage ample, for developingafilm such as that described upon developmentof an exposed silver halide in Jelley and Vittum U. S. Patent 2,322,027.emulsion in the presence of a color coupler, com- In certain cases, theS-hydroxyquinolines of prising an aqueous solution of sodium carbonate,our invention may be incorporated in the emul-2-amino-fi-diethylaminotoluene, sodium sulfite sion, overcoat, backinglayer or interlayer of a and approximately 0.25 gram per liter ofsoluim. tion of B-hydroxyquinoline-S-sulfonic acid. It will beunderstood that the examples and 4. A photographic developer havingreduced modifications included herein are illustrative only tendency tooxidation caused by heavy metals, and that our invention is to be takenas limited comprising an alkaline solution of a silver halide only bythe scope of the appended claims. developing agent, an alkali metalsulfite, an ali- What we claim is: phatic amine, and. a compoundselected from the 1. A photographic developing solution having classconsisting oi 8-hydroxyquinoline, S-hyreduced tendency to oxidationcaused by heavy droxyquinoline-fi-sulfonic acid and 8-hydroxymetals andcapable of forming a colored image quinoline-S-sulfonic acid substitutedwithamemupon development of an exposed silver halide ber of the classconsisting of halogen and alkyl. emulsion in the presence of a colorcoupler, comprising an alkaline solution of a primary am- ReferencesCited in the file of this Patent matic paradiamino developing agent, analkali UNITED STATES PATENTS metal sulfite, andS-hydroxyquinoline-E-sulfonic acid. Number Name Date 2. A photographicdeveloping solution having gg fig Ulnch et 53 195;?! reduced ndency tooxidation caused by heavy as i g 2, :2 metals and capable of forming acolored image 235243241 i i g- 950 upon development of an exposed silverhalide 2544649 g'fi g s i 1951 emulswn m the pr nce of a color coupler,com- 2,596,978 Burtner H May 20 1952 prising an alkaline solution of2amino-5-diethylaminotoluene, sodium sulfite, and8hydroxyquinoline-5-sulionic acid.

4. A PHOTOGRAPHIC DEVELOPER HAVING REDUCED TENDENCY TO OXIDIZATIONCAUSED BY HEAVY METALS, COMPRISING AN ALKALINE SOLUTION OF A SILVERHALIDE DEVELOPING AGENT, AN ALKALI METAL SULFITE, AN ALIPHATIC AMINE,AND A COMPOUND SELECTED FROM THE CLASS CONSISTING OF 8-HYDROXYQUINOLINE,8-HYDROXYQUINOLINE-5-SULFONIC ACID AND 8-HYDROXYQUINOLINE-5-SULFONICACID SUBSTITUTED WITH A MEMBER OF THE CLASS CONSISTING OF HALOGEN ANDALKYL.